Association between Leukemic Evolution and Uncommon Chromosomal Alterations in Pediatric Myelodysplastic Syndrome.

Background: Pediatric myelodysplastic syndrome (pMDS) is a group of rare clonal neoplasms with a difficult diagnosis and risk of progression to acute myeloid leukemia (AML). The early stratification in risk groups is essential to choose the treatment and indication for allogeneic hematopoietic stem cell transplantation (HSCT). According to the Revised International Prognostic Scoring System, cytogenetic analysis has demonstrated an essential role in diagnosis and prognosis. In pMDS, abnormal karyotypes are present in 30-50% of the cases. Monosomy 7 is the most common chromosomal alteration associated with poor prognosis. However, the rarity of specific cytogenetic alterations makes its prognosis uncertain. Thus, this study aimed to describe uncommon cytogenetic alterations in a cohort of 200 pMDS patients and their association with evolution to AML. Methods: The cytogenetic analysis was performed in 200 pMDS patients by G-banding and fluorescence in situ hybridization between 2000 to 2022. Results: Rare chromosome alterations were observed in 7.5% (15/200) of the cases. These chromosome alterations were divided into four cytogenetic groups: hyperdiploidy, biclonal chromosomal alterations, translocations, and uncommon deletions representing 33.3%, 33.3%, 20%, and 13.3%, respectively. Most of these patients (10/15) were classified with advanced MDS (MDS-EB and MDS/AML) and the initial subtype was present in five patients (RCC). The leukemic evolution was observed in 66.66% (10/15) of the patients. Most patients had poor clinical outcomes and they were indicated for HSCT. Conclusion: The study of uncommon cytogenetic alterations in pMDS is important to improve the prognosis and guide early indication of HSCT.

Prognostic Factors in Children and Adolescents with Lymphomas and Vertical Transmission of HIV in Rio de Janeiro, Brazil: A Multicentric Hospital-Based Survival Analysis Study.

Lymphomas related to HIV are generally aggressive and have a poor prognosis, despite the use of combined antiretroviral therapy (cART) and effective chemotherapy treatment. To determine survival and prognostic factors in children and adolescents living with HIV (CLWH) in Rio de Janeiro (RJ), Brazil, who developed lymphomas, we performed a retrospective and observational study of vertically infected CLWH aged from 0 to 20 incomplete years during1995 to 2018 at five reference centers for cancer and HIV/AIDS treatment. Of the 25 lymphomas, 19 were AIDS-defining malignancies (ADM) and 6 were non-AIDS-defining malignancies (NADM). The 5-year overall survival (OS) and 5-year event-free survival (EFS) probabilities were both 32.00% (95% CI = 13.72-50.23%), and the 5-year disease-free survival (DFS) probability was 53.30% (95% CI = 28.02-78.58%). In the multivariate Cox regression analysis, performance status 4 (PS 4) was considered a poor prognostic factor for OS (HR 4.85, 95% CI = 1.81-12.97, p = 0.002) and EFS (HR 4.95, 95% CI = 1.84-13.34, p = 0.002). For the DFS, higher CD4+ T-cell counts were considered a better prognostic factor (HR 0.86, 95% CI = 0.76-0.97, p = 0.017) in the multivariate Cox regression analysis. This study demonstrates, for the first time, survival and prognostic factors for CLWH who developed lymphomas in RJ, Brazil.

Incidence and Clinical Description of Lymphomas in Children and Adolescents with Vertical Transmission of HIV in Rio de Janeiro, Brazil, in Pre- and Post-Combined Antiretroviral Therapy Eras: A Multicentric Hospital-Based Survival Analysis Study.

The incidence of cancer in children living with HIV (CLWH) is high and lymphomas are the most common type of cancer in this population. The combined antiretroviral therapy (cART) changed the natural history of HIV infection. To determine the incidence and profile of these CLWH malignancies in Rio de Janeiro (RJ), Brazil, we conducted a retrospective and observational study of vertically infected CLWH, ranging from 0−20 incomplete years, from 1995 to 2018, at five reference centers. The study period was divided into three eras in accordance with the widespread use of cART in Brazil. 1306 patients were included. Of the 25 lymphomas found, 19 were AIDS-defining malignancies (ADM); 6 were non-AIDS-defining malignancies (NADM). The incidence rate (IR) of lymphoma developing was 1.70 per 1000 children-year (95% CI 1.09−2.50). ADM development IR decreased from 2.09−1.75−0.19 per 1000 children-year (p < 0.001) through cART eras. Cumulative Nelson−Aalen hazards of developing ADM over a 20-year period were 3.73% in the Early-cART era, 3.07% in the Mid-cART era, and 0.32% in the Late-cART era (p = 0.013). This study demonstrates the IR of lymphoma in CLWH in RJ, Brazil, as well as the benefit of cART in reducing ADM and death occurrence in the Post-cART era.

Clinicopathological and Immunohistochemical Study of Head and Neck Langerhans Cell Histiocytosis from Latin America.

Langerhans cell histiocytosis (LCH) is an inflammatory myeloid neoplastic proliferation with variable clinical behavior caused by the accumulation of CD1a+/CD207+ histiocytes, associated with a variable number of eosinophils, lymphocytes, plasma cells and multinucleated giant cells, most commonly observed in male children. LCH is uncommon in the head and neck region, occurring as ulcerated and reddened plaques or nodules that cause destruction of adjacent soft tissues and bone. The exact etiology of LCH is still unknown and controversial, with possible etiologic role of viruses, including Epstein-Barr virus (EBV). The aim of this study was to describe the clinicopathologic and immunohistochemical features of patients with LCH of the head and neck region. Clinical data from 19 patients with LCH were obtained from the archives of the Federal University of Rio de Janeiro and the Clinical Head and Neck Center of Guatemala. All cases were submitted to morphological, immunohistochemical analysis with CD1a, CD207, CD3, CD20, CD68, S-100 and Ki-67 and in situ hybridization for EBV. Ten cases were female and 9 male, with mean age of 11.5 years. Fourteen cases were located in the oral cavity, three cases in lymph nodes, and two cases in the scalp. In regard to the oral lesions, 13 cases were intra-osseous with six cases in anterior mandible, five cases in posterior mandible, and two cases in posterior maxilla while one case was located exclusively in the gingiva. The inflammatory pattern showed variation in the number of plasma cells, eosinophils and lymphocytes, while tumor cells were positive for CD1a, S-100 and CD68 in all cases, and positive for CD207 in 18 cases. In situ hybridization for EBV were negative in all cases.

Congenital Langerhans cell histiocytosis: a good prognosis disease?

Langerhans cell histiocytosis is rare and more frequent in children. The skin is affected in 50% of the cases and is the only site in 10%. Its course varies from self-limited and localized forms to severe multisystemic forms. Congenital cases are usually exclusively cutaneous and self-limited, with spontaneous remission in months. This study presents a rare congenital case, initially restricted to the skin, with subsequent dissemination and fatal outcome. A male newborn presented congenital disseminated erythematous scaly lesions. The biopsy was conclusive for Langerhans cell histiocytosis. The patient evolved into the multisystemic form in weeks, when chemotherapy was started, according to the LCH-2009 protocol; however, the patient was refractory to treatment and died.

Congenital Langerhans cell histiocytosis: a good prognosis disease?

Abstract: Langerhans cell histiocytosis is rare and more frequent in children. The skin is affected in 50% of the cases and is the only site in 10%. Its course varies from self-limited and localized forms to severe multisystemic forms. Congenital cases are usually exclusively cutaneous and self-limited, with spontaneous remission in months. This study presents a rare congenital case, initially restricted to the skin, with subsequent dissemination and fatal outcome. A male newborn presented congenital disseminated erythematous scaly lesions. The biopsy was conclusive for Langerhans cell histiocytosis. The patient evolved into the multisystemic form in weeks, when chemotherapy was started, according to the LCH-2009 protocol; however, the patient was refractory to treatment and died.